NYQUIST WAVELENGTH DIVISION MULTIPLEXING SYSTEM

摘要

PROBLEM TO BE SOLVED: To utilize Nyquist WDM to transmit signals, thereby realizing high-spectral efficiency over long distances.SOLUTION: Aspects of the present invention include apparatus and methods for transmitting and receiving signals in communication systems. A beam splitter splits an optical signal into a plurality of signals. At least one QPSK modulator generates a plurality of QPSK modulated signals from the plurality of signals. An optical multiplexer combines the plurality of QPSK modulated signals into a multiplexed signal. The multiplexed signal is then transmitted.